Nylon, as a polymeric material, is one of the most widely known and most versatile polymers in industry. Synthetic thermoplastic polymers characterized as polyamides are generally known as nylons. Discovery of the first nylons arose out of the classic researches of W. H. Carothers in 1928. Carothers et al. were researching for new synthetic fibers. In the course of this research, they discovered that the condensation products of diacids with diamines gave long-chain polymers with the desired properties. The first nylon to be developed commercially was the condensation product of hexamethylene diamine and adipic acid, called nylon 66. Since that early discovery, a large family of nylons have been prepared by a number of processes. Nylons are still highly prized for their utility in synthetic fibers and, in addition, are used in a wide variety of applications.
One of the features of the present invention is the discovery that the blending in solution of two different nylons: The first (P1), a crystalline (high molecular weight nylon 66); and the second (P2) an amorphous binder nylon (such as the multipolymer 66/610/6), results in membranes with burst strengths and flexibilities which are significantly higher than those which are observed for membranes consisting of Type 66 or Type 6 nylon homopolymers. This is accomplished without any loss in the filtration properties of the resultant membranes.